This population based study will evaluate the significance of the EEG as a predictor for recurrence of seizures in those children who have had a simple febrile convulsion. Outcomes reported are febrile seizure recurrence and afebrile seizure occurrence. The evolution of the EEG pattern will be described, and patterns will be correlated with the clinical outcome. The clinical study is being carried out in Skopje, Yugoslavia, at the Pediatric Clinic of the University of Skopje. The study began in FY 1982 and final follow-up visits will be completed in FY 1991. Patient accrual was completed in December, 1984, by which time approximately 400 patients with a febrile seizure, no prior complex or multiple seizures and with a normal or nonspecific abnormal EEG, were registered into the study and began the study protocol and follow-up. An additional 300 patients with a specific abnormal EEG were entered for baseline information and follow-up. Data editing and file creation are continuing. After an on-site review visit, it was determined that additional efforts by the clinical center were needed to collect data from those patients lacking a return visit and those who did not have return visits after 24 months following study entry. This will facilitate study of long-term recurrence of febrile seizures, change in EEG, and the predictive qualities of EEG for febrile seizure occurrence. The extended follow-up effort is now in progress. Statistical analysis of baseline EEG and its association with characteristics of the child and family and the clinical characteristics of the seizure has been completed and a manuscript has been submitted for publication. The master file, including follow-up data at all visits for all patients, should be completed in FY 1991, at which time further analyses will be undertaken.